This project extends the parental proposal devoted to general problems of multilocus dynamics on the special but very important case of the dynamics of quantitative traits influenced by multiple genes under selection. Main aims of it are the development of advanced approaches to mathematical analysis of multilocus quantitative traits, the study of the peculiarities of genetic variability, its maintenance and evolution in populations under selection, the evolution of recombination among multiple loci affecting quantitative variability under selection, and the effect of selection on quantitative traits determined by multiple genes and culturally transmitted parental phenotypes. In order to reach these aims, we will analyze a general multilocus dynamics with selection function that includes non-additive epistatic interactions among loci using perturbation techniques, apply the approach to the analysis of non-additive quantitative traits and traits showing genotype-environment interactions, further develop our finding in the evolution of recombination among multiple selected loci for the case of quantitative traits, and consider special important cases of general dynamics mode proposed by me and the foreign co-investigator for the evolution of gene-culture interaction. We will use both analytical and computer simulations approaches, to solve problems described.